efe-epaNew Delhi

People in the Indian capital of New Delhi are now only a click away from asking for blood of a specific type and quantity thanks to the "Donor on Call" app developed by the NGO Green Shakti Foundation.

According to data from India's Ministry of Health, the country needs around 13 million units of blood annually but currently falls short of 9 million units.

Since the end of 2014, a growing army of donors have been fighting to turn the tide through the mobile app, which is aimed at facilitating the donation process and preventing blood from expiring before it can be used.

Pratap Chandnani, the founder of the NGO and one of the app's developers, explained that close to 30 percent of blood donated ends up getting wasted.

On his mobile screen, red dots on a map showed registered donors with the requested blood type located less than 10 kilometers (6 miles) from the medical center of reference.

To register to the app, all people need is an Android phone, an altruistic spirit and good health.

Users can benefit from the system themselves or use it for their friends or family members by filling in a simple form, which even takes into account people's dietary preferences.

Chandnani said it is a matter of luck as to how fast a response comes in.

Sometimes, users are able to find several matches in a matter of seconds, while on other occasions there is not a single response.

However, for those unable to find a match, the app also has an option to call nearby donors.

Mohit Varma, 34, an associate consultant at a multinational tech company, saw first-hand how the app can transform lives.

He learned of the case of a 10-year-old boy with a cardiovascular disease and the rare blood type A(-) who had to be moved to a hospital in Noida, near the capital, to undergo open heart surgery.

The child's family, who hailed from South India and had no contacts in the North, were desperate, prompting Varma to launch a campaign through the app in which he managed to collect 14 units of blood in a single day, and 35 units in total.

With more than 6,000 registered users already, Varma's is just one of many success stories from the app, which hopes to see even more as it continues to grow.